Rotary engine.



' w. VON P ITTLBR. ROTARY ENGINE.

I APPLIOATION FILED HA3. 3, 1910. v 988,591 Patented Apr.4, 1911.

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w. VON PITTLBR.

ROTARY ENGINE.

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Patented A r. 4, 1911.

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WILHELM VON PITTLER, OF WILMERSIDORF, NEAR BERLIN, GERMANY.

ROTARY ENGINE.

Specification of Letters Patent.

Patented Apr. 4, 1911.

Application filed March 3, 1910. Serial No. 547,127.

To all whom it may concern:

Be it known that I, WILHELM voN PITT- LER, a subject of the King ofPrussia, residing at Wilmersdorf, near Berlin, Ger.- many, have inventedcertain new and useful Improvements in Rotary Engines, of which thefollowing is a specification.

The present invention relates to a rotary engine preferably intended forelastic fluids.

The object of the invention is to construct an engine in which allinfluence of centrifugal forces is obviated and in which means areprovided for controlling the abutments so precisely that the clearancespaces are reduced to a minimum. To obtain the first of these objectsthe engine, which in its general characteristic features correspondswith the engines described in U. S. Patent No. 894,391 differs from thispatent in the fact that the grooved part is fixed and consequently theslides arranged in the radial or axial grooves have no peripheral butonly a radial or axial movement, the rotating piston being fitted on arotating drum or disk and engaging into the circular grooves. Forcontrolling the slides rotating cams are fitted on the shaft of theengine, said cams acting on the slides by suitable means. For obtainingthe second object the means provided for controlling the abutment slidesconsist of a combination of fluid pressure controlling means and ofmechanically acting means; thus relieving on the one hand the mechanicalcontrolling means by an additional fluid pressure and on the other handavoiding the lack of reliability of the fluid pressure controlling meansby the positive action of the mechanical means.

In the drawin various designs of the present invention intended to serveas steam engines are exemplified in the preferable radial type, in thesedrawings Figures 1 and 2 being one design shown in vertical crosssection and in horizontal section. Figs. 3 and 4 show a modified detailin two different designs; Figs. 5 and 6 represent another design of theengine in cross section and in horizontal section; Fig. 7 is a detail ofthe latter engine. Fig. 8 shows a particular arrangement of the fluidpressure controlling means.

The engine according to Figs. 1 and 2 has fitted on shaft 1 a disk ordrum 2 with projections 3 on its sides, which projections engage inconcentric grooves 6 provided on the inside of the face walls or heads 5of the cylinder 4. In each head 5 a further radial groove 7 has been cutcrossing the grooves 6, an abutment slide 8 being fitted in said groove7. The abutment slides 8 are provided with notches 9, which correspondwith the grooves 6 and can be brought to temporarily cover the same bythe movement of the abutment slide, in order to allow of the pistons 3passing, the solid parts of the abutment slides covering and overlappingthe grooves. The controlling of the abutment slides 8 is obtained bymeans of cam action in combination with the action of a pressure medium,say steam. Each abutment slide 8 is provided for this purpose with aroller 10 on an inward extension 8, which roller engages in the grooveof a cam 11 revolving together with disk 2; furthermore each slide iscoupled at its outward end by means of a rod 12 leading toward outsideand a transverse member 13 with the rod 1 1 of a piston 14 reciprocatingin a steam cylinder 15. Any well known mechanism may be used to supplypressure medium, or steam to the slide actuating cylinder, and to thisend I have shown connected to the two ends of the cylinder 15, pipes 37and 38 joined to the casing of a cook or valve 32, to which cook orvalve is also connected a steam supply pipe 34.- and a vent pipe 39. Theplug 33 of this cook 32 is provided with a lever 30 having a slot 31 inwhich engages a pin 29 on a slide rod 28. This rod is mounted insuitable supports a and carries a roller 27 engaging in a cam groove 26'in a cam 26 mounted on the shaft 1 of the engine. The plug 33 has twopassages 35 and 36, Figs. 2 and 2", Fig. 2 showing the position of plug33 when the parts of the engine are in their positions as shown in Fi'2, and Fig. 2 showing the position of t e plug when its lever 30 is inthe dotted line position Fig. 2. The structure is such that actuatingfluid is admitted simultaneously to one side of the piston and ventedfrom the other, and vice vei'sa. Any other mechanism may be used toaccomplish this end. In order to avoid too great clearance spaces it isnecessary to return the abutment slides 8 as closely as possible behindthe passing pistons into their inner position in which they shut off thegrooves 6. WVhen a cam controlling gear is employed very steep curveshave to be used, which will necessarily produce noxious shocks. Theseshocks may, however, be avoided if according to the present inven tionthe cam gear is relieved by the additional use of the action of apressure medium. It might seem advisable to effect the control of theabutment slides 8 merely by means of a pressure medium without the useof cam gears; such mode of controlling the slides would, however, notafford a sufficient reliability; in case of a refusal the pistons wouldstrike against the abutment slides, whereby the whole engine would beseriously damaged. By a simultaneous use of the cam action, however, theproper movement of the abutment slides is absolutely safeguarded.

If the engine is to rotate in one direction only, the backward branch 11of the inside curve of the cam 11, considered in the direc tion ofrotation, may be made quite steep (say radial) Fig. 3, so that theabutment slides 8 may be returned into their closing position by theaction of the pressure medium independently of the shape of the outercurve, and if necessary quite suddenly and close behind the piston 3. Inthe same manner according to Fig. 3 also the front branch of the outercurve can be dispensed with, if the reversibility of the engine isforfeited. If the engine is to be reversible the curves in the cams 11will have indeed to vbe quite symmetrical, as shown in Fig. 1,

provided there are not two sets of cams arranged as in Figs. 5 and 6 forthe ahead and backward rotation.

It may under certain conditions be. desirable to stop the engineautomatically in case the pressure medium control should fail. For suchpurpose it is only necessary to entirely leave away the outer curve ofthe cams, as shown in Fig. 4, so that the abutment slides 8 are indeedmoved by the inner curve in an outward direction into the positionopening the grooves 6, but not back again into their closing position.In consequence thereof the steam pressure cannot act and the engine willstop automatically. The concentric part 11" Fig. 4, of the outer rim ofthe cam may be left, so that the roller 10 traveling over the same andtherewith the abutment slide 8 are kept in the open position. Thisconcentric part of the cam may however also be dispensed with accordingto Figs. 5 and 6.

If the advantages of the shape of the inner curves of the cam shown inFig. 3 are to be utilized for a reversible engine a separate set of camswill have to be provided for each direction of rotation. Such an engineis represented in Figs. 5 and 6. Here two cams 11 and 11 of reverseshape are provided for each abutment slide 8. The shape of cam 11 isevident from Fig. 5, the shape of cam 11 from Fig. 7 both cams beingseen in the same direction. .11 for each slide 8 are fitted on a commonsleeve 16 or 16 respectively adjustably but not rotatably fitted on theextension boss 2 of the piston disk or drum 2. The two sleeves 16, 16are coupled with each other by means of bolts 17 passing through holes18 in disk 2. The sleeve 16 is provided at its outer end with a groove19, in which a bifurcated lever 20 engages. The extension 8 of theabutment slides 8 are fitted with rollers 10, 10 on both sides; ofwhich, according to the direction of rotation, the one 10 or the other10* works together with the respective cam 11 or 11*. lever 20 issuitably coupled in such a manner to the gear for reversing the steam,that on the steam being reversed the cams are exchanged at the sametime.

In the engine according to Figs. 5 and 6 the controlling of each of theslides 8 by the pressure medium is independent, a separate controllingpiston 21 being provided for each slide. In the design shown in Fig. 8each slide 8 has likewise its separate pressure medium controlling gear.inder 22 has been cast on each head 5. Through a slot 25, which connectsthe groove 7 with the inside of the cylinder 22, a dog 8 provided onslide 8 engages in a slot 24 in the piston 23 movable in cylinder 22.Also two or more abutment slides 8 may be provided on either side of theengine in an equidistant arrangement along the periphery of the engineand the number of the pistons 3 may be accordingly increased. Hereby theshaft may be entirely freed from any onesided pressure on the bearing.The increase The bifurcated Here a cyl- I The two cams 11 and of thenumber of the pistons and slides is, V

however, to a certain degree limited by the consideration due to theexpansion. By symmetrically arranging the working grooves 6 on bothsides of the piston disk or drum 2 a total relief can be obtained in anaxial direction.

Instead of running the engine with single expansion, as shown, it may bealso constructed as a multiple expansion engine, by arranging the singlegrooves 6 in a suitable manner behind each other or in groups.Furthermore the grooves on the two sides may be of different sectionalarea, whereby the grooves of the smaller sectional area would be usedfor the first expansion stage. The increase of the sectional area of thegrooves would be possible by increasing the depth, of the grooves, theirwidth and the stroke of the slides being maintained; how ever thegrooves on one side might also be made wider, in which instance ofcourse the abutment slide 8 would have to be controlled by separatecylinders for the pressure medium according to Figs. 5 and 6 or Fig. 8,owing to the difference of their stroke.

Having thus described my invention what I claim and desire to secure byLetters Patent of the United States is:

1. In a rotary engine the combination of a rotary member fitted withpistons, a number of concentric annular grooves for the pistons in thecylinder, an abutment slide across the annular grooves said slide havingnotches so as to allow a free passage for the pistons, and means forcontrolling said abutment slide.

2. In a rotary engine the combination of a rotary member fitted withpistons, a number of concentric annular grooves for the pistons in thecylinder, abutment slides across the annular grooves, said slides havingnotches so as to allow a free passage for the pistons, and means forcontrolling said abutment slides.-

3. In a rotary engine the combination of a rotary member fitted withpistons on its face, a number of concentric grooves for the pistons inone head of the cylinder a radial abutment slide across the annulargrooves, said slide having notches so as to allow a free passage for thepistons, and means for controlling said abutment slide.

4:. In a rotary engine the combination of a rotary member fitted withpistons on each face, a number of concentric grooves for the pistons ineach head of the cylinder, a radial abutment slide across each set ofannular grooves said slides having notches so as to allow a free passagefor the pistons, and means for controlling said abutment slides.

5. In a rotary engine for elastic fluids the combination of a rotarmember fitted with pistons, a number oi? concentric annular grooves forthe pistons in the cylinder, an abutment slide across the annulargrooves said slide having notches so as to allow a free passage for thepistons, and means for controlling the abutment slide both mechanicallyand by the action of fluid pressure.

6. In a rotary engine for elastic fluids the combination of a rotarymember fitted with pistons, a number of concentric annular grooves forthe pistons in the cylinder, an abutment slide across the annulargrooves said slide having notches so as to allow a free passage for thepiston, a pressure fluid cylinder, a piston in said cylinder andoperatively connected with the abutment slide and a cam revolving withthe rotary member and being in operative connection with the abutmentslide.

7 In a rotary engine for elastic fluids the combination of a rotarymember fitted with pistons, a number of concentric annular grooves forthe pistons in the cylinder, an abutment slide across the annulargrooves, said slide having notches so as to allow a free passage for thepistons, a pressure fluid cylinder, a piston in said cylinder andoperatively connected with the abutment slide, and a revolving groovedcam being in operative connection with the abutment slide and having theouter rim of the groove cut away at the part of the cam producing theoutward movement.

8. In a rotary engine for elastic fluids the combination of a rotarymember fitted with pistons, a number of concentric annular grooves forthe pistons in the cylinder, an abutment slide across the annulargrooves, said slide having notches so as to allow a free passage for thepistons, a pressure fluid cylinder, a piston in said cylinder andoperatively connected with the abutment slide, and a revolving groovedcam being in operative connection with the abutment slide and having theouter rim of the groove cut away at its eccentric portion.

9. In a rotary engine for elastic fluids the combination of a rotarymember fitted with pistons, a number of concentric annular grooves forthe pistons in the cylinder, an abutment slide across the annulargrooves, said slide having notches so as to allow a free assage for thepistons, a pressure fluid cy inder, a piston in said cylinder andoperatively connected with the abutment slide, a separate revolvinggrooved cam of reverse shape for each direction of rotation and meansfor bringing one or the other cam into operative connection with theabutment slide.

10. In a rotary engine the combination with a rotary member fitted withpistons; of a cylinder having grooves in which the pistons travel, anabutment slide having passages therein for the pistons, and means atopposite ends of the slide to cause its passages to move into and out ofregister with the grooves.

11. In a rotary engine the combination with a rotary member havmg apiston therein; of a cylinder having a groove therein in which thepiston travels, an abutment slide having a passage for the piston,mechanical means at one end of said slide and fluidactuated means at theother end thereof to simultaneously control movement of the slide withrespect to said groove.

12. In a rotary engine, the combination with a rotary member having apiston thereon and its shaft; of a cylinder having a &

groove therein in Which the piston travels, an abutment slide having apassage for the piston, a cam on the shaft acting on one end of theslide and fluid pressure means at the other end of the slide tosimultaneously con trol the movement of the slide with respect to saidgroove.

13. In a rotary engine for elastic fluids, the combination With a rotarymember having a piston on each side thereof, a cylinder having groovesin Which said pistons travel, a radial abutment slide on each side ofthe in presence of two Witnesses.

WVILHELM VON PITTLER.

Witnesses ALFRED NUTTING, RIPLEY WILSON.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

